Guards for fluorescent light tubes



Aug. 24, 1954 E. SCHNEIDERMAN GUARDS FOR FLUORESCENT LIGHT TUBES Filed May 31, 1950 GLM - INVENTOR. Eu AfiEl/NE/DERMAN Patented Aug. 24, 1954 ED STATES PTiENT OFFICE GUARDS FOR FLUORESCENT LIGHT TUBES Eli Schneiderman, Hillside, N. J. Application May 31, 1950, Serial No. 165,179

2 Claims.

This invention relates to improvements in the guards for fluorescent light tubes.

It has been found that known guards designed to prevent the luminous tubes of fluorescent light fixtures from being jarred out of the sockets are not suitable for the tubes of greatest diameter, such as those of Nil-watts, although the accidental falling thereof is even more hazardous than in the case of tubes of smaller diameter. It has been further found that known guards are also impractical in that type of installation having the tubes arranged end on end over rows of work benches or machines as well as in those cases where the end of a tube is close to the end of the reflector. I

It is an object of the instant invention to provide a guard suitable for a fluorescent light tube of relatively large diameter.

A further object is the creation of a guard readily adapted to installations having a series of tubes mounted end on end.

Another object is the creation of a guard for the end of a tube in close proximity to the end of a reflector.

Other objects of the instant invention will become apparent in the course of the following specification.

In the attainment of these objectives, the improved guard is made in three embodiments. In the first, the guard is designed for use with the known porcelain sockets of lilo-watt tubes where a flange near the top of the socket prevents the attachment of known guards. The 100-watt tube sockets further have two openings extending between the mounting and back surfaces and intermediate the flange and the top of the tube. Utilizin the two openings, the improved guard is an L-shaped spring strip having at the top of the vertical portion a horizontal portion or strip through which openings are made to register with the openings in the socket, the strip being affixed to the back of the socket by any suitable fasteners inserted through the aligned openings. The bottom or stem of the L-shaped guard is extended inwardly under the socket to support an apertured resilient ring, the aperture being upwardly directed for fitting around the bottom and sides of the tube. In the second embodiment, the improved guard is a dual unit having left and right hand apertured resilient rings for removable insertion over opposite sides of adjacent tubes inserted in sockets mounted back to back, the guard being attached around the two sockets by a collar. In the third embodiment, the improved guard is designed for 2 removable attachment around a tube from the side for those cases where the end of the tube in the reflector allows "insufficient space for using known guards, that is those sprung downwardly.

The invention will appear more clearly when taken in connection with the accompanying drawings showing by way of example preferredembodiments of the inventive idea.

In the drawings:

Figures 1 through 4 show the first embodiment of the improved guard, constructed in accordance with the principles of this invention, and in which:

Figure 1 is a front view of the improved guard;

Figure 2 is a sectional view along 2-2 of Figure 1;

Figure 3 is a plan view of the guard shown in Figure 1; and

Figure 4 is a perpective view of the guard shown in Figure 1 assembled with a tube and a socket.

Figures 5 through 8 show the second embodiment of the improved guard in which:

Figure 5 is a. front elevational View of the improved guard;

Figure 6 is a side view of the guard shown in Figure 5;

Figure 7 is a plan view of the guard shown in Figure 5; and

Figure 8 is a perspective view of the improved guard shown in Figure 5 in assembly with the tubes and sockets;

Figures 9 through 10 show the third embodiment of the improved guard in which:

Figure 9 is a plan view of the improved guard; and

Figure 10 is a view in perspective showing the uard assembled with the tube and socket in a reflector.

Referring now in greater detail to the first embodiment of the improved guard designed primarily for tubes of relatively large diameter and shown in Figures 1 through 4 where like reference numerals indicate like parts, reference numeral it indicates the socket, II the fluorescent light tube, and 12 the guard.

The socket H3 is of the known porcelain type having a rectangular cross section in which the front mounting surface is spaced parallel to a back surface and further having spaced parallel side surfaces. In the front mounting surface at the bottom is a vertical slideway terminating in a circular recess in which the electrical contacts of the tube are inserted. Also in the front surface but at the top are the usual horizontal re I the bottom and sides of the tube I I cesses for flanges (not shown) while intermediate the flanges and the top of the circular recess are two openings between the front and back surfaces.

The fluorescent light tube II is also of known type being equipped with the usual end contact pins but is of relatively large diameter as in the case of the loo-watt tube. Only one end of the tube I I has been shown since the opposite end is identical. When installing the tube II in the socket II), the end pins of the tube are turned vertically for insertion through the vertical slideway until the top pin is at the top of the circular recess in which position rotary motion of the tube brings the pins into releasable engagement with the electrical contacts. Vibration sometimes causes the pins to work loose and the tube to slip out of the socket unless caught by some device which is the function of the following described guard I2.

Due to the flanges in the recesses of the socket, known guards are not'adapted for attachment by the usual collar around the top of the socket and to move the collar downwardly would interfere with the end of the tube when inserted. To solve the problem, the L-shaped guard I2 has been formed from strips of resilient material, the vertical portion or stem I3 being designed to be superposed on the back surface of the socket III with the horizontal ring holder I4 passing under the base and extended forwardly thereof (Fig. 4). At the top of the stem [3 is the resilient strip I5 secured by any suitable means and with the longitudinal center line perpendicular to the longitudinal center line of the stem I3. The strip I5 is attached to the back of the socket ID as follows: Through each end of the strip openings I6 and I! (Fig. 1) are made and so positioned as to be aligned with the previously mentioned openings extending through the socket. Through each set of aligned openings, a screw I8 is inserted and fastened on the inner face of the socket by a nut. In this way, the

end of the ring holder I l can be pulled down- 1 wardly to the dot and dash position shown in Figure 4 and will return to the full line position when released. On the free end of the ring holder It the resilient ring I9 with upwardly directed aperture is spot welded for fitting around as illustrated to prevent it from falling out when and if the pins should be jarred out of the sockets.

In operation, the guard I2 is attached to the socket of the tube in the manner previously described. Assume that it is desired to replace the tube II in the fixture, by pulling downwardly on the ring holder IA of the guard I2, the circular prongs of the apertured ring I9 will be pulled away from the base and sides of the tube II whereupon the pins of the tube can be rotated for alignment with the vertical slideway in the socket and one end of the tube removed. The opposite end of the tube is removed in a like manner. When inserting another tube, the steps are reversed, that is the ring I9 is forced downwardly and rearwardly so that the end of the tube II with the pins aligned with the socket slideway can be first pushed upwardly and then rotate through some 45 to bring the pins into electrical contact with the contacts of the socket. By releasing the apertured ring, it will move upwardly to the normal position shown by the full lines in Figure 4. If necessary, the prongs of the ring may be forced apart to aid in fitting the collar around the tube. If due to vibration, the

pins of the tube should work loose from the electrical contacts of the socket and the end of the tube falls out, it will be sustained by the apertured ring until reinstalled but without the guard the loosened tube would constitute a hazard to anyone in the immediate vicinity.

In the second embodiment of the improved guard shown in Figures 5 through 8, reference numeral M (Fig. 8) indicates two similar sockets mounted back to back, 4| two similar fluorescent light tubes installed in the sockets for an end on end installation, and 42 the dual guard.

The sockets are of known type for tubes of less wattage than the tubes described in the first embodiment and have suflicient space between the top of the tube and the top of the socket for the attachment of the collar of a guard. However, the dual guard 42 is a radical departure from known similar devices as will be noted in the following paragraph.

The dual guard 42 is formed from strips of resilient material and is constituted of a resilient collar 43 of sufficient size and proper shape to be fitted around the tops of the two known sockets 40 as illustrated in Figure 8, the sockets being mounted back to back and the collar held in place by a screw 46a through aligned openings in the outwardly directed ears of the collar as illustrated, the screw being threaded at one end. for the attachment of a nut. Extended downwardly from each side member of the collar 43 are the resilient stem members 44 and G5 which at the bottom have attached thereto the horizontal resilient ring holders, 36 and ll, offset from the ends of the tubes H as illustrated and extended in opposite directions along opposite sides of the tubes and parallel to the longitudinal center lines thereof. At the end of each of the ring holders are the apertured resilient rings 48 and 69, respectively, similar in all respects except that the apertures are turned in opposite directions toward the sides of the tubes. Any suitable means may be used for the attachment of the stems 44 and 45 to the collar 63 as well as the ring holders 46 and ll to the stems and for the attachment of the apertured rings to the ring holders.

In operation, assuming that the sockets 40 are mounted as shown in Figure '7 and it is desired to attach the dual guard 42, with the screw 44 removed from the ears, the collar 43 of resilient material can be spread around the tops of the two similar sockets and the screw 44 reinserted and fastened in place with a nut. If fastened as shown in Figure '7, the apertured ring 48 will be directed in one direction and the like ring 49 in the opposite direction. By swinging the rings to the dotted positions shown in Figure '7, one at a time, the tubes 4| can be inserted in the sockets in the manner described for the first embodiment. Moving the prongs of the rings apart for fitting around the tubes and permitting a return to the normal full line position (Figs. 7 and 8) the dual guard will hold each tube against slipping out of the sockets and in a mounting position of the tubes in which the guard of the first embodiment or the like could not be operated.

In the third embodiment of the guard shown in Figures 9 and 10, reference numeral 66 indicates the socket, 6I the fluorescent light tube, 62 the reflector, and 63 the guard.

The socket and the tube 6| are similar in all respects to like members of the second embodiment, previously described.

The guard 63 is substantially similar to the previously described guard 42 of the second embodiment except that only one apertured ring 64 is used.

In operation, at the end of a. tube or a row of tubes covered by a reflector, the end of the reflector 62 is too near the end of the tube 6| for the use of the guard of the first embodiment which must have sufiicient space to be swung rearwardly and, of course, the dual guard 42 of the second embodiment would be very much in the way. But, the guard 63 with one apertured ring 64 can be attached to and detached from the tube from the side and without interference with the refiector.

It will be noted in each of the three embodiments, that the portion of the body of the ring holder adjacent the fixed end is offset from the socket and that the portion of the holder on the side of the tube or at the free end of the holder is longitudinally tangent to or directed along or adjacent or against or extended along the surface of the tube.

It will be understood that the invention is not limited to the exact disclosure herein described but may lend itself to a variety of expressions within the scope of the appended claims.

What is claimed is:

1. A dual guard for the tubes of fluorescent lights in combination with adjacent sockets for releasably supporting successive tubes end on end, each socket having a. front mounting surface and a back surface spaced parallel from the front member and spaced parallel side surfaces, the adjacent sockets being mounted back to back intermediate two successive tubes; the guard comprising a resilient collar for the adjacent sockets, the collar comprising integrally formed, spaced, front and back members and spaced parallel side members coacting with corresponding surfaces of the adjacent sockets, one of the members of the collar having an opening formed therein with integrally formed and outwardly turned ears adjacent the opening, means coacting with the ears for securing the collar to the sockets, a resilient stem disposed on each side member of the collar, the stem being extended downwardly therefrom along the side of the socket substantially to the center line of the tubes when inserted, a resilient ring holder disposed on the bottom of each stem, the ring holders being ofiset from the ends of the tubes and oppositely directed adjacent opposite sides of the tubes in a plane parallel to the longitudinal center lines thereof, a resilient apertured ring disposed on the free end of each ring holder with the aperture directed toward the side of the tube.

2. In combination with sockets located between two successive tubes of fluorescent lights, a dual guard for said tubes, said guard comprising a collar for mounting upon said sockets, two resilient stems disposed on opposite sides of the collar, each stem being extended downwardly from the collar along a side of the socket substantially to the center lines of the tubes when inserted, a separate resilient ring holder disposed on the bottom of each stem, the ring holders being oppositely directed adjacent opposite sides of the tubes, and a separate resilient apertured ring disposed on the free end of each ring holder.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,446,461 Diver Aug. 3, 1948 2,448,236 Schneiderman et al. Aug. 31, 1948 FOREIGN PATENTS Number Country Date 576,706 Great Britain Apr. 16, 1946 

